Well tubing calipering and recording device



Sept. 11, 1951 P. E. CHANEY ET AL 7,

WELL TUBING CALIPERING AND RECORDING DEVICE Filed Aug. 7, 1946 2 Sheets-Shet 1 m a f m m. 3M E n I n6 N 0 0 1 7 ii 1 4 Mg .m h d 2 //V//A////// 4// #27 7/////// 7///z m w K 3 llmnn lfilill lillJ fi I I I 1 1 1: mn J W 6 vru 3 U wn l eP 1951 P. E. CHANEY ETAL WELL TUBING CALIPERING AND RECORDING DEVICE Filed Aug. 7, 1946 2 Sheets-Sheet 2 A m a m m 2 E adN mm m .1 mud n 27/1/44! 1 EB T x m n V A 0 JM MPH \7//// 7 //A\////// Patented Sept. 11, 1951 WELL TUBING CALIPERING AND RECORDING DEVICE Preston E. Chaney and William E. Barnes, Beaumont, Tex., assignors to Sun Oil Company, Philadelphia, Pa a corporation of New Jersey Application August 7, 1946, Serial No. 689,038

3 Claims. (Cl. 33-178) 1 The present invention relates to a calipering and recording device for indicating accurately the internal surface conditions of pipes, tubes and like conduits. The device has special utility in the determination of variations from the normal of internal surface configurations and internal circumferences of extended lengths of conduits, particularly oil well tubing containing fluids under pressure, during the recording operation.

It is generally appreciated that oil and gas well tubing becomes worn and corroded after periods of use, depending upon the operating conditions to which it is submitted. Many wells produce, in addition to oil and gas, water having a high acidic content which actively attacks and corrodes the tubing resulting in the formation of pits and depressions on the internal surfaces of the tubing. In addition to corrosion, scoring and wearing of the internal surfaces of the tubing is caused by the passage of well tools through the tubing and by the presence of foreign materials in the fluid flow. The indentations in the tubing walls resulting from the scoring and corrosion of the well tubing are sometimes so severe that the wall thickness of the tubing is reduced to such an extent that it cannot withstand the pressure of fluids flowing therethrough. Consequently, the tubing becomes ruptured .necessitating its removal after the damage has been done. To prevent such failure of the'well tubing it is desirable periodically to determine the condition of the interior of the tubing walls in order that replacements can be made or proper precautions taken to prevent rupture of the tubing.

Calipering devices which usually involve the application of electrical circuits, are now available for measuring variations in the internal surfaces of well tubing. However, devices of this type are not very well adapted for measuring and recording variations in the internal surfaces of well tubing under pressure due to the prac. tical difliculties incident to using electrical cables and other electrical equipment which are required to effect the recording.

The present device is entirely mechanical in operation and is so constructed that it is readily operated with available equipment which is customarily used in auxiliary well operations, for example, such equipment as is used in tool "fishing, well surveying, etc.

It is a principal feature of this invention to provide a calipering device which may be lowered or dropped as a unit by a suitable wire line into the tubing of a well under pressure and effect figuration of the tubing as the device passes upwardly therethrough. After the device is removed from the tubing the continuous record is examined and from this record defective tube lengths which must be removed and replaced are readily and accurately determined.

This is made possible by the design and arrangement of the calipering or feeler mechanism. This mechanism comprises a plurality of independently operated elements each 'of which is actuated in accordance with any pit or depression which is encountered as the calipering unit is passed through the tubing. Upon the actuation of any of the calipering elements a stylus which is positioned in recording relation to a chart will be operated and consequently each independent it or depression is recorded. This chart, by preference, will be cylindrical and caused to rotate as the calipering unit is passing through the tubing. By arranging the calipering elements to be independently operable, variations from the normal radius of the tubing will be indicated, that is, as a pit or depression is encountered the calipering elements independently enter such pit or depression and record the variation from the normal radius of the tubing on the recording chart.

In addition to being independently operable the calipering elements or feelers will operate in unison when variations in the internal circumference of the tubing are encountered. When the calipering elements operate in unison a record will be made by the stylus to indicate this variation which will show a decrease or increase in the circumference. This latter function of the calipering elements is very important in the practical use of this invention, particularly when the device is used for calipering connected sec tions of tubing, since the jointures of the tubing will be indicated by variations in the internal circumference. Such variations will be of substantially equal magnitude and will appear at substantially equally spaced points on the recording chart. 7 For example, consider well tubing of extreme lengths such as from five to ten thousand feet, which for example, is made up in thirty foot sections joined together by internal or external collars. As the calipering unit is passed through the tubing and the joints are encountered, the calipering elements, acting simultaneously, will be forced inwardly or outwardly as a group, depending on whether the couplings for the tube sections. are inside or outside couplings. Each time the calipering-elemeat; encounter a coupling of the well tubin the stylus member will be actuated substantially the same distance and the indications on the chart will be similar and equidistant, assuming the tube sections are of the same length. Therefore, the number of sections-through which the calipering unit has passed as well as the particular section or sections which are corroded or pitted can be readily determined from the recording chart.

It will be understood from the above that the calipering portion of the unit is arranged to provide two complemental functions. An operator of the instrument can caliper tubing wells of great depths and also determine, from the recording chart the exact location of all pits or depressions encountered within the tubing particularly those which may be considered hazardous to the further operation of the well tubing. It will further be seen that the caliperin unit is designed to permit its construction to be varied for calipering different sizes of well tubing and that it is particularly adapted by its construction and arrangement of cooperating parts to be used with well tubing which is operated under high pressures.

It is a principal object of this invention, therefore, to providea calipering device which may be lowered as a unit into a well tubing under pressure and effect a continuous recording of the variations of the internal surface configuration of the tubing in order that the location of corroded areas and other conditions of wear existing along the entire length of the tubing can be deter mined.

Another object of this invention resides in the provision of a calipering and recording device which is completely self-contained and mechanically operated, and does not require the use of insulated electric cables or the like, it being necessary only to lower the caliperin device into the well and then pull it back to obtain a complete and continuous record of the internal surface of the well tubing.

It is also an important object of this invention to provide a calipering device for measurin and recording the changes in the inside radius of the well tubing at the joints where the tubing sections are coupled together, thereby enabling an operator to determine the exact location of pits or depressions which are encountered.

It is a further important object of this invention to, mechanically operate the recording chart and stylus point in response to mechanical movement originating through contact of the calipering device against the internal surface of the well tubing as the mechanism is raised or lowered in the well.

Further objects and advantages of the invention will be apparent by reference to the following specification and drawings, in which:

Fig. 1 is a longitudinal section of the upper end of the calipering device.

Figs. 2, 3 and 4 are respectively longitudinal section views in continuation of Fig. l and which taken together with Fig. 1 show the complete calipering unit.

Fig. 5 is a detail of an element shown diagrammatically in Figs. 2 and 3 rotated through 90 counterclockwise in the plane of the paper.

Fig. 6 is a view on the line 6-6 of Fig. 3.

The calipering device of this invention is comprised generally of an elongate cylindrical member which, for purposes of our discussion, can be tion which is shown in detail in Fig. 1 contains provisions for attaching a solid steel line of small diameter for lowering and raising the assembly in the well tubing. Operation in either direction is possible, 311168 the device may be constructed to permit calipering of the well tubing either as it is lowered into the tubing or raised out of the well although the usual procedure is to permit calipering while the instrument is being raised out of the well. Since the device is particularly adapted for calipering tubing under high pressure, the use of the thin wire line as a means for raising and lowering the housing permits the tubing to be securely packed at its inlet end, for example, by the use of conventional packing rings. The second section of the housing contains the mechanism which operates the stylus and includes the feelcr devices which engage the walls of the tubing to transmit the variations in the internal surfaces of the tubing under examination to the stylus point which makes a clear record upon a rotating chart or recorder member. The third section of the elongated housing comprises the portion of the device which transmits the rotary movement to the cylindrical chart or recorder member and here asafety device isincorporated to prevent damage to the rotating mechanism. The lower section of the housing contains the mechanism which drives the recorder member above it. As the assembly is raised or lowered in the well tubing, the drive mechanism friction wheel engages the inner walls of the well tubing to rotate the recorder member or chart. At the same time, the feelers or stylus actuators at the upper end of the device engage the walls, moving the recording stylus in reciprocation to effect the record of variations in the internal surface of the tubing under examination. The cooperation of the stylus and recording chart mechanism with each other is such that a spiral record is produced, and changes in internal radius or depressions on the internal surfaces are indicated by angular deviations from a true spiral line.

Referring to Fig. 1 a swivel connection indicated generally at S is constructed of upper and lower cooperating sleeves in and H which are threaded together as a unit and also threadedly secured to the upper end of the main housing H of the calipering device as indicated. The swivel connection is adapted to receive a measuring line L by means of which the calipering unit is dropped into the well tubing and the connection is so designed as to prevent the measuring line from becoming twisted during the dropping or calipering operation. The upper sleeve l0 terminates in a cap portion l2 which is drilled axially for the reception of a suitable measuring line L. The lower sleeve II is also drilled axially to receive a stub shaft 13 having an aperture l4 adjacent its upper end for securing the measuring line thereto. At its lower end the stub shaft is flanged outwardly at l5 and the sleeve I I is recessed to retain roller bearings I6 which are received by the flanged lower end of the stub shaft. The above described swivel device is no part of the present invention as this element is readily available on the market but is described as showing one auxiliary element having utility with the device of the present invention.

The present calipering unit is an improvement over or refinement of our co-pending applications Ser. No. 624,811, filed October 26, 1945 (nowPatent No. 2,518,663) and Ser. No. 624,813, filed October 26, 1945, and functions generally in a mandivided roughly into four parts. The upper sec.- ner similar to the inventions disclosed in these applications. Parts of the present invention are common to the above mentioned applications but the present invention contains several modifications or improvements thereover.

In Figs. 2 and 3 of the drawings, a cylindrical member adapted to receive a recording chart and thus function as a chart holder is indicated at and is positioned generally centrally of the tubular member H. Extending axially of the chart holder 20 is a stylus arm or stylus actuator 2| having at its lower end a stylus holder or housing 22. The chart holder 20 is threaded at its upper end to housing H at threaded connection C, and is provided with lower end wall 23 which cooperates with a clutch mechanism, later to be described for preventing damage to the instrument in case its movable parts become jammed. Shaft 24 is rotated by drive wheel 25 shown in Fig. 4

I through siutable gearing by maintaining drive wheel 25 in frictional contact with the tubing inner wall by spring loaded wheel 26. The wheels 25 and 26 are positioned at the lower end of the calipering unit and the wheel 26 is spring pressed against the wall of the tubing by means of a pivoted bracket 21 and spring 28 while the wheel 25 is rotatably mounted at 29 in a manner to maintain constant contact with the tube wall and through gear trains 30 and 3| respectively to rotate the shaft 24. During rotation of the chart holder 20 it will move downwardly .of housing H through the cooperating action of threads T on the inner wall of the housing H and threads in connection C.

In our co-pending application Ser. No. 624,811 (now Patent No. 2,518,663), heretofore mentioned, a clutch drive mechanism is described which permits rotation of the chart holder during normal operation or until the chart holder has reached its limit of movement longitudinally of housing H after which upon further rotation of the shaft 24 through the gear and wheel arrangement above described the clutch mechanism will function to prevent rotation of the chart holder and hence prevent injury to the gear trains, etc. even though the drive shaft is rotating. In the present invention this general clutch drive mechanism is further modified to overcome minor difliculties encountered in the use of the device disclosed in the aforesaid application. l?

Referring to Figs. 3 and 6, the drive mechanism comprises a sleeve 32 which receives the upper end of drive shaft 24 and a collar 33 in turn is fixed to sleeve 32 by means of a set screw 34,. The shaft 24 is grooved or splined at U-U and the collar 33 is provided with a pair of cooperating wheels 35 having ribs 36 thereon which are receivedin the grooves of shaft 24 and as the shaft 24 is rotated, the grooved connection with the ribs 36 of collar 33 provides rotation of the chart holder 20 through the spring pressed plungers 31 which are received in indentations in the top of the chart holder end wall 23 during normal operation. However, when the chart holder 20 has reached its lower limit of movement spring pressed plungers 31 will function as a slipping clutch and the collar 33 will rotate freely on the chart holder end wall 23.

The rollers 35 on collar 33 provide a rolling frictional connection with shaft 24. This arrangement constitutes an improvement over our previously disclosed sliding frictional grooved connections since any small particles of grit or dirt which became lodged in the sliding frictional grooved connections would interfere with and frequently lock the connection against sliding action which resulted in stopping of rotation of the chart holder and consequent destruction of the gear train. With the present rolling frictional contact this 'difllculty is overcome.

Referring to Fig. 2, the calipering mechanism comprises a plurality of caliper elements or feelers which are rotatably mounted on pivoted bell crank levers 5|. In order to provide a rigid construction for maintaining the calipering elements or feelers in operative and aligned relation with the other elements of the calipering apparatus a hollow sleeve 52 is provided having at its lower end a screw threaded portion 53 and at its upper end terminates in a drilled out portion indicated at 54. The sleeve member 52 is joined to the housing H by means of a conh'ecting plug 55 having upper and lower screw threaded end portions 56 and 51 for securement respectively to the calipering sleeve 52 and the housing H. The sleeve 52 is provided with a series of slots 58 which extend circumferentially thereof and are designed to receive the crank lever arms 5| and thecaliper elements or feelers 50. The calipering elements or feelers 50 during operation will pivot inwardly and outwardly through the slotted openings 58 as the calipering unit is passed through tubing and in contact with its walls. As indicated, each of the bell crank lever arms is provided with a spring 60 in order to urge each of the caliper feeler elements outwardly and a single spring BI is provided for operating a plunger 62 to urge simultaneously all of the caliper elements outwardly in contact with tubing being calipered.

The plug member 55 is drilled to receive the stylus actuating rod 2| having the stylus housing 22, heretofore referred to, fixed thereon at its lower end and its upper end positioned within the caliper sleeve 52 and maintained by a spring 66 in contact with the inner arms. of the bell crank levers. Spring 66 is not as strong as springs 60 and 6| in order that the feelers 50 will be maintained in operative relation with the tubing wall.

As the calipering unit is passed through tubing to be calipered the chart holder will be rotated as heretofore explained and during its rotation will move downwardly at a rate depending on the pitch of the threads T on the inner wall of the housing and simultaneously therewith the calipering elements or feelers 50 will independently function in accordance with any individual nits or depressions which are encountered in the tube wall to operate the stylus actuator 2| which in turn moves the stylus housing 22 longitudinally of the recorder member or chart previously inserted in the chart holder 20 and as iointures between tube sections are encountered all of the calipering elements will operate simultaneously to move the stylus actuator.

The recorder member or chart is constructed of thin sheet metal with a coating provided thereon which is removed by the stylus movement and in effect etche's the record on the chart as the stylus is actuated through the caliper elements 50. The metal foil recording chart is preferably inserted into the chart chamber by wrapping about .the periphery of a cylindrical insertion plug of suitable diameter, and inserting this assembly into the chart holder 20 in such manner that the metallic foil recording chart assumes the contour of the inner wall of the chart holder, and preferably so that the edges of the chart form a snug butt joint which serves accuse 7. to hold the chart in position after the insertion plug has been withdrawn.

It has'heretofore been found difiicult to maintain uniform pressure of the stylus against the chart surface and in order to overcome this difflculty a stylus holder is provided by which uniform pressure may at all times be maintained on the chart. For an understanding of this particular feature of the invention reference is had to Fig. 5 which is shown rotated at an angle of 90 degrees counterclockwise in the plane of the paper from its assembled position in Figs. 2 and 3. The stylushousing 22 has at one end a pair of cooperating sleeves l and II respectively which are removably secured together in screw threaded relation. The inner sleeve H receives the stylus 12 while the outer sleeve is adapted for frictional sliding movement within the housing. A spring 73 and set screw 14 are positioned at the opposite end of the housing to provide an arrangement i'or maintaining the desired pressure on the stylus point 12.

In order to assemble and disassemble the callpering unit it is, of course, desirable that provision be made to prevent marring the recording chart and to this end the stylus housing is pro vided with means for retracting the stylus point from the recording chart. Referring again to Fig. 2 the connecting plug 55 between the caliper holding sleeve 52 and the housing H is provided with an on" center longitudinally drilled out portion to receive a rack 80 and a retractor arm BI- is positioned within the chart chamber and is joined at its upper end to the rack while its lower end terminates adjacent the stylus housing 22 as shown clearly in Fig. 5. The sliding sleeve 10 is slotted to receive one arm 82 of a pivoted bracket while the other arm 83 of the bracket is positioned in abutting relation with the upper end of ejector rod 8|. In order to retract the stylus 12 from contact with the chart a rack key 84 (Fig. 2) is insertable through a radial aperture 85 in the connecting plug 55 to effect actuation of the ejector arm 8|.

The sleeve, or chart holder drive bushing 32, is,

modified over that disclosed in our co-pending application, Ser. No. 624,813, filed October 26, 1945, in order to permit the caliper elements or feelers 50 (Fig. 2) to be retracted as the calipering device is lowered into the well tubing prior to the actual calipering operation. It will be appreciated, of course, that if the calipering ele- -ments or feelers 50 are permitted to rotate as the calipering device is dropped into the well tubing undue wear would occur to these elements. The sleeve 32 is provided with an upstanding flange 90 and a thrust bearing assembly 9| shown diagrammatically including thrust plate 92 fitted into the area defined by the flange 90. This arrangement permits the thrust bearing to contact the stylus housing 22, forcing the stylus rod 2| upwardly against the calipering elements, lever arms causing the feelers 50 to be retracted into housing 52 and out of contact with 8. pering. The distance that the instrument moves to release the feeler wheels is negligible, being of the order of one half of one percent of the total tubing surveyed and this unsurveyed section can be surveyed by additional or overlapping runs.

What we claim and desire to protect by Letters Patent is:

1. A tube calipering and recording device which comprises a cylindrical housing, a plurality or automatically retractable calipering arms mounted adjacent one end of said housing, a spring for urging simultaneously all of said calipering arms radially outwardly during operation to an equal predetermined extent from said housing to center the device and contact the normal inner wall of tubing being calipered, a separate spring for each of said calipering arms for urging them independently outwardlyv beyond the predetermined extent to contact irregular surface configurations while calipering, a cylindrical recording chart holder having a chart therein, said chart holder having simultaneous rotative and axial movement, a splined drive shaft for operating said chart holder, a clutch connecting said shaft to said chart holder, means for limiting the movement of said chart holder toward said calipering arms, a rigidly supported recording instrument having a stylus therein in said housing non-rotatably positioned in cooperative relation with said chart, a centrally disposed reciprocating rod engaged adjacent one end by said calipering arms, said rod being reciprocated-by movement of any of said calipering arms beyond the predetermined extent to record on said rotative and axially movable chart, said recording instrument being rigidly mounted adjacent the other end of said reciprocating rod and positioned within said recording chart holder, said chart holder having a base which, when said chart holder approaches its limit of axial movement in a direction toward said calipering arms, will contact the recording instrument end of said rod and urge the same toward said calipering arms and thereby retract all of said calipering, arms from contact with the tube surface.

2. In an internal tube wall calipering and recording device adapted to be passaged through an extended length of tubing the combination comprising am elongated housing, a cylindrical recorder member, a holder carrying said member and mounted in said housing for simultaneous rotative and longitudinal movement therein, driving means for said holder. a stylus member positioned in scribing relation with said recorder member, a plurality of calipering members spaced circumferentially of said housing and adapted for lateral movement in response to surface irregularities of the tube wall being calipered, said calipering members each being retractable from the tube wall, a mechanical actuator mounted for reciprocal movement within the housing and engaged at one end by said calipering members and at the other end by said stylus member, means for resiliently urging said calipering members toward contact with the tube wall, means for limiting the longitudinal movement of said recorder member toward said calipering members, and means carried by said holder for pushing said actuator in opposition to said urging means as the recorder member approaches said limit of longitudinal movement and thereby retracting the calipering members.

3. In an internal tube wall calipering and recording device adapted to be passaged through an extended length of tubing the combination comprising an elongated housing, a cylindrical recorder member, a holder carrying said member and mounted in said housing for simultaneous rotative and longitudinal movement therein, driving means for said holder, a clutch between said driving means and said holder, a stylus member positioned in scribing relation with said recorder member, a plurality of calipering members spaced circumferentially of said housing and adapted for lateral movement in response to surface irregularities of the tube-wall being caliperedhsaid calipering members each having an inwardly extending part and an outwardly projectivej part retractable from the tube wall, a mechanical actuator mounted for reciprocal movement within the housing and engaged at one end by said inwardly extending parts and at the other end by said stylus member, means for resiliently urging the outwardly projective parts of said calipering members toward contact with the tube wall and the inwardly extending parts toward abutment with said actuator, means for limiting the longitudinal movement of said recorder member toward said calipering members, and means carried by said holder for pushing said actuator in a direction toward the callpering members as the recorder member approaches said limit of longitudinal movement and thereby urging said outwardly projective parts toward retracted position.

PRESTON E. CHANEY. WILLIAM E. BARNES.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 222,292 Luders Dec. 2, 1879 236,257 Quimby Jan. 4, 1881 526,383 Dale Sept. 25, 1894 630,145 Hawley Aug. 6, 1901 713,784 Mellor Nov. 18, 1902 1,339,955 Hardel May 11, 1920 1,440,798 Revega Jan. 2, 1923 1,805,343 Robbins May 12, 1931 1,919,332 Jones July 25, 1933 2,078,623 Wilde Apr. 27, 1937 2,102,080 Kinley Dec. 14, 1937 2,235,533 Roberts Mar. 18, 1941 2,267,110 Kinley et al. Dec. 23, 1941 2,322,343 Brandon June 22, 1943 OTHER REFERENCES 

